3v3 is far too easy and more vulnerable to boosting rather than solo que or 5s. Its fine if they get the borders while they are doing 3s but don't let them get it for solo que or 5s.Just because they got platinum in 3s does not mean they are functional in solo que or 5s because they haven't earned it for that que.
Being Bronze in Team 3v3 doesn't really help your argument that it's "Easy" - http://www.lolking.net/summoner/na/44153184
The border you get from ranked 3s doesn't (or shouldn't) be displayed while doing solo queue or ranked 5s. It should only be displayed only when doing ranked 3s, normal 3s (provided it's higher than your solo queue border), and custom/ARAM/Dominion games (provided that it's higher than both your solo queue and ranked 5s border).
